1. Field of the Invention
The present invention relates to a structure of touch display panel and, more particularly, to a liquid crystal display touch panel structure.
2. Description of Related Art
In modern society, a liquid crystal display (LCD) device with touch control function has played an important role for the current consumer electronic product, such as the smart phone, digital camera and tablet computer.
In order to provide the LCD device with the touch control function, it is generally to first manufacture a touch panel and an LCD device separately and then combine them together so as to enable the LCD device to have the touch control function. That is, a typical touch display panel is provided with the touch control function by overlapping the LCD device with a touch panel, as the LCD device itself does not have any touch control function.
On-cell and in-cell touch technologies were thus invented to overcome the drawbacks of traditional touch technology described above. The on-cell technology is to dispose sensors on the back side of a color filter substrate to form a completed color filter substrate. One of the on-cell touch technologies is provided to dispose touch sensors on a thin film and then bond the thin film onto the upper one of the two substrates. The in-cell technology is to dispose the sensors within the LCD cell structure. That is, the in-cell touch technology is provided to integrate the touch sensor within the display unit so that the display unit is provided with the ability of the touch panel. Therefore, the touch display panel does not need to be bonded with an additional touch panel so as to simplify the assembly procedure. Such skill is generally developed by TFT LCD manufactures.
In US patent publication 2011/0193820 entitled “touch screen”, the horizontal scan row electrodes and the vertical data column electrodes of a thin film transistor (TFT) layer on a TFT LCD panel are used as the driving/sensing conductor lines in a touch control system, so as to eliminate the need of additional driving/sensing conductor layer thereby reducing the cost. However, such a skill may encounter problems when the actual structure of TFT LCD panel is considered. In actual TFT LCD panel, the horizontal scan row electrodes and the vertical data column electrodes are disposed on a TFT layer, while the TFT layer is disposed on a lower glass substrate and a common electrode layer made of transparent metal is formed on the bottom of an upper glass substrate. As a result, when user's finger touches the upper glass substrate, the horizontal scan row electrodes and the vertical data column electrodes are unable to effectively sense the finger's touch because of being shielded by the common electrode layer made of transparent metal, resulting in unsatisfactory touch coordinate calculation. Therefore, it desired for the aforementioned touch display panel system to be improved.